Knitted casing for inflatable bladder

ABSTRACT

A KNITTED CASING IS PROVIDED FOR A BLADDER WHICH, WHEN INFLATED, HAS THE SHAPED OF A SOLID OF REVOLUTION, E.G., AN ELONGATED NECK TERMINATING IN AN APPROXIMATELY SPHERICAL BULGE OF MUCH LARGER DIAMETER. THE CASING IS MADE BY KNITTING PANELS ON A FULL-FASHIONED KNITTING MACHINE IN SUCH A MANNER AS TO PRODUCE IN EACH PANEL THE CURVATURE   OF THE BULGE. THE PANELS ARE THEN STITCHED TOGETHER ALONG THEIR EDGES BY A FULL-FASHIONED SEAMER TO COMPLETE THE CASING.

March 2, 1971 GORDON E ZTAL v 3,567,562

KNITTED CASING FOR INFLATABLFBLADDEK Filed Sept. 27', 1967 FIG. 4

BARNETT D. GORDON Y STEVE E. SOLTIS ATTORNEYS I NVENTORS United StatesPatent 3,567,562 KNI'I'IED CASING FOR INFLATABLE BLADDER Barnett D.Gordon, Brookline, and Steve E. Soltis,

Worcester, Mass., assignors to M.K.M Knitting Mills,

Inc., Manchester, N.H.

Filed Sept. 27, 1967, Ser. No. 670,839 Int. Cl. B32b 3/10 US. Cl. 161-73 Claims ABSTRACT OF THE DISCLOSURE A knitted casing is provided for abladder which, when inflated, has the shape of a solid of revolution,e.g., an elongated neck terminating in an approximately spherical bulgeof much larger diameter. The casing is made by knitting panels on afull-fashioned knitting machine in such a manner as to produce in eachpanel the curvature of the bulge. The panels are then stitched togetheralong their edges by a full-fashioned seamer to complete the casing.

The invention relates to a knitted casing for a bladder which is to beinflated by air or gas under considerable pressure, the inflated shapeof the bladder as confined by the casing being that of a solid ofrevolution such as a sphere, cylinder, cone, combinations of theseshapes, or solids having profiles consisting of arbitrary shapes.

More particularly the invention relates to a casing for a bladder whichwhen inflated is part of a floating buoy.

For oceanographic observations floating buoys are employed which whendropped in the water are automatically inflated by air or gas at severalpounds pressure to the square inch. To contain the bladder when inflatedto such pressures, a strong casing is required. For this purpose panels(preferably three) of strong yarn, are knitted, the knitting being doneon a full-fashioned knitting machine in such a manner that each panel,not only has the correct edge contour but also has a three-dimensionalshape conforming to any spheroidal portion or portions which the bladdermay be designed to have when inflated.

.For a more complete understanding of the invention reference may be hadto the following description thereof, and to the drawing, of which FIG.1 is an elevational view of a knitted casing embodying the invention;

FIG. 2 is a plan view of a single panel to be assembled with othersimilar panels to form the casing shown in FIG. 1;

FIG. 3 is a perspective view of the casing when enclosing an inflatedbladder; and

FIG. 4 is a perspective view of a casing having another shape.

The casing illustrated in FIGS. 1 and 3 is made by joining togetherthree panels such as that illustrated in FIG. 2. Each panel 12 is formedwith a suitable threedimensional bulge so that when the three arestitched together along their side edges, the bulges form the smoothcurved surface of a solid of revolution, each panel being completelyformed by knitting operations on a full-fashioned machine. The sideedges of the panels are joined by a full-fashioned seamer with stitchesfine enough to catch all of the end loops of the knitted course at theselvages. By using a strong yarn such as stretch nylon for the knittingand seaming, a reliably strong casing 1s 3,567,562 Patented Mar. 2, 1971formed to contain a bladder when inflated suddenly to a pressure oftwelve pounds or so to the square inch.

The curvature of the three-dimensional bulge of each panel is determinedby the operation of the yarn carriers and narrowing fingers of afull-fashioned knitting machine.

By way of example, the panel shown in FIG. 2 of the drawing can be madeas follows.

Starting at the lower end 14 of the panel 50 courses are knitted on 86needles. Then the narrowing fingers and yarn carriers narrow the fabricby four needle spaces, this being followed by four courses of plainknitting. This narrowing operation is repeated four times, thus reducingthe number of active needles to 70. Then follow 142 courses of plainknitting, after which the narrowing fingers begin a widening operationat 16, the end points of the mutually adjacent ends of the two narrowingfingers being spaced apart by four needle spaces. In each widening stepthe narrowing fingers dip twice and move away from each other thusdenuding four needles, which take yarn again from the carrier when itmakes its next pass. The stroke of the carrier is increased two needlespaces at each end after each widening step so that the total number ofneedle wales in the fabric is increased by four. After each of the firstfive widening steps ten courses are knitted, the narrowing fingers beingreturned to their initial positions. After each of the next twelvewidening steps eight courses are knitted, the narrowing fingersreturning each time to their initial positions. In the subsquentwidening steps, beginning at 18, the narrowing fingers do not returntoward each other after the loop-shifting operations. Eight courses areknitted after each of the first three of these widening steps. Sixcourses are knitted after each of the next ten steps, and four coursesafter the next eight steps. The next three steps are followed by 12, 26and 26 courses respectively.

After the next and final widening step, at 20, forty courses are knittedon 238 needles, after which a narrowing operation begins at 22, thenarrowing fingers moving progressively toward each other, each narrowingstep consisting of two needle inward loop-shifting movements of eachnarrowing finger, accompanied by decrease of the stroke of the yarncarrier by two needle spaces at each end, this being followed by anoutward movement of each narrowing finger one needle space. Each of thefirst two narrowing steps is followed by the knitting of eight courses.The next step is followed by six courses; each of the next twenty-eightsteps by three courses; each of the next ten steps by four courses; eachof the next two steps by six courses; and each of the next two steps byeight courses. The final narrowing step at 24 reduces the number ofactive needles to 54 which carry on plain knitting for 594 courses tothe upper end 26 of the panel. When the three panels are stitchedtogether the upper portion of the resulting casing will be cylindrical.If a slight tapering of this portion is desired, the correspondingportion of each of the panels can readily be tapered by gradualnarrowing.

The panels are joined, wrong side out, by stitching on a full-fashionedseamer using nylon thread. The stitches are overedge (US. Standard #503,two-thread) and are close together so that the seams are very strong.After the stitching is done, the casing is ready for assembly with theother parts of the device for which it is made, but may if desired beturned inside out.

The foregoing is a specific example of a casing designed for use as apart of an inflated floating buoy. Other shapes for other purposes canbe made as, for example, the shape with a double bulge illustrated inFIG. 4 of the drawing.

We claim:

1. A knitted fabric bladder casing having a spheroidal portioncomprising:

a plurality of knitted courses defining a plurality of like panels, eachpanel having at least one three-dimensional bulge, the selvage profileof each panel described by a plurality of end loops; and

strand means operatively connected through correlative end loops ofadjacent panels for holding said adjacent panels in fixed spacedrelation to each other, said bulge of each panel forming the curvatureof said spheroidal portion.

2. The casing as claimed in claim 1 wherein said plurality of knittedcourses are full-fashion knitting machine courses.

3. The casing as claimed in claim 1 wherein said strand means is afull-fashion seamer strand.

References Cited UNITED STATES PATENTS PHILIP DIER, Primary ExaminerU.S. Cl. X.R.

